The Republican-led House Oversight and Government Reform Committee has opened a formal investigation into the Wikimedia Foundation over alleged, coordinated manipulation of Wikipedia articles. In a letter dated Aug. 27, Committee Chairman James Comer and subcommittee chair Nancy Mace asked Wikimedia’s chief executive, Maryana Iskander, to turn over documents, communications and internal analyses related to “foreign operations and individuals” who may have edited entries to influence U.S. public opinion. The lawmakers cite a March 2025 Anti-Defamation League report that found widespread antisemitic and anti-Israel bias across multiple language editions of Wikipedia. They also reference separate research alleging pro-Kremlin editing campaigns. The Committee is seeking records of possible coordination by nation-state actors, universities that receive federal funds, and other organized groups, as well as identifying information—such as names, IP addresses and activity logs—of volunteer editors sanctioned by Wikipedia’s Arbitration Committee. A Wikimedia Foundation spokesperson said the nonprofit has received the request and will cooperate, adding that the organization is committed to safeguarding the integrity and neutrality of the online encyclopedia. The probe underscores growing congressional concern that disinformation injected into Wikipedia can ripple across the internet and be incorporated into artificial-intelligence systems that rely on the site’s vast trove of free content.